Auto sizing chuck

ABSTRACT

A chuck includes a chuck body extending along a longitudinal axis, the chuck body including a plurality of slots each arranged at an oblique angle with respect to the longitudinal axis. A plurality of jaws each includes a first engagement portion, a jaw end, and a drive end. Each of the jaws is disposed within one of the plurality of slots and is movable between a close position and an open position. A biasing member is coupled to the plurality of jaws and is operable to bias the plurality of jaws toward the close position and a rotating assembly is selectively engageable with the plurality of jaws such that when engaged, the plurality of jaws are movable in response to rotation of the rotating assembly.

RELATED APPLICATIONS

This application is a continuation of prior-filed, co-pending U.S.patent application Ser. No. 13/440,542, filed Apr. 5, 2012, now U.S.Pat. No. 9,283,625, which claims priority to U.S. Provisional PatentApplication No. 61/472,057, filed on Apr. 5, 2011, and U.S. ProvisionalPatent Application No. 61/509,779 filed on Jul. 20, 2011. The entirecontents of each of these documents are incorporated herein byreference.

BACKGROUND

The present invention relates to an auto sizing chuck for use with adrill or other tool. More specifically, the invention relates to a chuckthat automatically adjusts to the size of the tool inserted into thechuck.

SUMMARY

In one embodiment, the invention provides a chuck that is adjustablebetween a closed or minimum open position and a maximum open positionwithout rotation of the chuck. The chuck includes a plurality ofthreaded jaws and a threaded rotating assembly that is selectivelyengageable with the jaws. When the jaws and the rotating assembly aredisengaged, the jaws are free to move between the minimum open positionand the maximum open position. When the jaws and the rotating assemblyare engaged, the rotating assembly must be rotated to tighten the jaws.

In one construction, the invention provides a chuck for a power tool.The chuck includes a chuck body extending along a longitudinal axis, thechuck body including a plurality of slots each arranged at an obliqueangle with respect to the longitudinal axis. A plurality of jaws eachincludes a first engagement portion, a jaw end, and a drive end. Each ofthe jaws is disposed within one of the plurality of slots and is movablebetween a close position and an open position. A biasing member iscoupled to the plurality of jaws and is operable to bias the pluralityof jaws toward the close position and a rotating assembly is selectivelyengageable with the plurality of jaws such that when engaged, theplurality of jaws are movable in response to rotation of the rotatingassembly.

In another construction, the invention provides a chuck for a powertool. The chuck includes a chuck body extending along a longitudinalaxis, the chuck body including a plurality of slots each arranged at anoblique angle with respect to the longitudinal axis and a plurality ofjaws each including a first engagement portion, a jaw end, and a driveend, each of the jaws disposed within one of the plurality of slots andmovable between a close position and an open position. A biasing memberis coupled to the plurality of jaws and is operable to bias theplurality of jaws toward the close position and a rotating assembly iscoupled to the chuck body and includes a second engagement portion. Therotating assembly is rotatable with respect to the chuck body between adisengaged position, an engaged position, and a tightened position,wherein the first engagement portions and the second engagement portionare disengaged when the rotating assembly is in the disengaged positionsuch that the plurality of jaws are movable along the longitudinal axisindependent of the rotating assembly and wherein the first engagementportions and the second engagement portion are engaged when the rotatingassembly is in the engaged position such that the plurality of jaws aremovable along the axis in response to rotation of the rotating assembly,and wherein rotation of the rotating assembly from the engaged positionto the tightened position moves the plurality of jaws toward the closeposition.

In yet another construction, the invention provides a method of engaginga tool in a chuck. The method includes movably positioning a pluralityof jaws within a chuck body, the jaws movable between a close positionand an open position, disengaging a rotating assembly from the pluralityof jaws, and moving the jaws to the close position in response to thedisengagement of the rotating assembly from the plurality of jaws. Themethod also includes pushing the jaws toward the open position until thetool can be positioned within the jaws, biasing the jaws toward theclose position such that the jaws lightly hold the tool in a desiredposition, and rotating the rotating assembly to engage the rotatingassembly and the plurality of jaws. The method also includes furtherrotating the rotating assembly to force the jaws toward the closeposition to firmly hold the tool in the desired position and maintainingthe position of the rotating assembly to hold the plurality of jaws inthe desired position.

Other aspects of the invention will become apparent by consideration ofthe detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a broken away view of an auto sizing chuck in a firstposition;

FIG. 2 is a section view of the chuck of FIG. 1 in a second position;

FIG. 3 is a perspective view of a bottom cover;

FIG. 4 is a perspective view of a chuck body;

FIG. 5 is a side view of the chuck body of FIG. 4;

FIG. 6 is a section view of the chuck body of FIG. 4 taken along a planethrough the longitudinal axis of the chuck body;

FIG. 7 is a perspective view of a guide sleeve;

FIG. 8 is a perspective view of a jaw;

FIG. 9 is a perspective view of a sleeve;

FIG. 10 is a perspective view of a collar;

FIG. 11 is a perspective view of a split ring; and

FIG. 12 is a broken away view of another auto sizing chuck in a firstposition.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the following drawings.The invention is capable of other embodiments and of being practiced orof being carried out in various ways.

FIGS. 1 and 2 illustrate an auto sizing chuck 10 that is capable ofquickly receiving many different tools having different diameters. Thechuck 10 includes a bottom cover 15, a chuck body 20, a sliding assembly25, and a rotating assembly 30. The bottom cover 15, illustrated in FIG.3 includes a cup-shaped member having an aperture 35 formed in abottommost surface 40. The aperture 35 is threaded to receive the chuckbody 20 to fixedly attach the bottom cover 15 to the chuck body 20.

FIGS. 4-6 illustrate the chuck body 20 which includes a shaft portion45, a collar portion 50, and a head portion 55. The shaft portion 45extends along a longitudinal axis 60 and includes external threads 65arranged to threadably engage the threaded aperture 35 of the bottomcover 15 to attach the bottom cover 15 to the chuck body 20. The collarportion 50 and the head portion 55 cooperate to define a slot 70therebetween. The slot 70 includes a tapered surface 75 that extends aportion of the way between the collar portion 50 and the head portion55.

In the illustrated construction, three jaw apertures 80 extend throughthe collar portion 50 and into the head portion 55. Each of theapertures 80 is spaced about 120 degrees from the adjacent two apertures80 and is angled at about 15 degrees with respect to the longitudinalaxis 60. As one of ordinary skill in the art will realize, additionalapertures 80 or fewer apertures 80 could be used if desired. Inaddition, different angular spacing and a different angle with respectto the longitudinal axis 60 could be employed if desired.

FIG. 6 illustrates the interior of the chuck body 20 which includes athreaded bore 85 and a central bore 90 extending from the threaded bore85. The threaded bore 85 includes threads that are sized and arranged toattach the chuck 10 to a power tool or other device for use. Asillustrated in FIG. 3, the three jaw apertures 80 extend through thecollar portion 50 and into the central bore 90 within the head portion55.

With reference to FIGS. 1 and 2, the sliding assembly 25 includes aguide sleeve 95, three jaws 100, three jaw pins 105, and a biasingmember 110. As illustrated in FIG. 2, the biasing member 110 includes acompression spring disposed between the guide sleeve 95 and the bottomcover 15 and arranged to bias the guide sleeve 95 away from the bottomcover 15. It should be noted that the invention is described asincluding three jaws 100 and three jaw pins 105. However, otherconstructions may use fewer jaws 100 or more jaws 100, thereby requiringfewer or more jaw pins 105. Thus, the invention should not be limited toconstructions that employ only three jaws 100.

The guide sleeve 95, illustrated in FIG. 7 includes a cylindricalportion 115 and a collar 120 disposed at one end of the cylindricalportion 115. A bore 125 extends through the cylindrical portion 115 andis sized to allow the guide sleeve 95 to slide along the shaft portion45 of the chuck body 20. The collar portion 120 extends around one endof the cylindrical portion 115 and provides a surface that engages oneend of the biasing member 110. Three apertures 127 extend radially intothe collar 120 and are sized to receive the jaw pins 105.

FIG. 8 illustrates one of the jaws 100. Each jaw 100 includes a body 130that extends along a jaw axis 135 and includes an engaging surface 140at one end and a pin aperture 145 near the opposite end. The pinaperture 145 is sized to receive the jaw pin 105 such that the jaw 100is free to slide along the jaw pin 105. The engaging surface 140 isangled with respect to the jaw axis 135 at an angle that is about equalto the angle of the jaw apertures 80 with respect to the longitudinalaxis 60. Thus, in the illustrated construction, the engaging surface 140is angled at about 15 degrees with respect to the jaw axis 135. Thisarrangement assures that the engaging surface 140 remains substantiallyparallel to the longitudinal axis 60 at all positions. A guide surface150 is formed opposite the engaging surface 140 and is contoured toengage the central bore 90 of the chuck body 20 to guide the movement ofthe jaw 100 along the longitudinal axis 60. A recessed surface 155extends from the guide surface 150 to the second end of the jaw 100 andincludes a threaded portion 160.

The rotating assembly 30 includes a split ring 165, a collar 170, and asleeve 175 that rotate together about the longitudinal axis 60. Thesleeve 175, illustrated in FIG. 9 includes a first cylindrical wall 180and a second smaller diameter cylindrical wall 185 that cooperate toform a hollow tube-like member. The smaller diameter cylindrical wall185 is sized to fit within the bottom cover 15 and engages the cover 15such that the sleeve 175 is rotatable with respect to the bottom cover15 but is not movable along the longitudinal axis 60 with respect to thebottom cover 15. In another construction, the bottom cover 15 and thesleeve 175 are fixedly attached to one another such that both componentsrotate in unison about the longitudinal axis 60.

As illustrated in FIG. 10, the collar 170 includes a cylindrical outerwall 190 sized to fit within the first cylindrical wall 180 of thesleeve 175 to couple the sleeve 175 and the collar 170 for rotation. Thecollar 170 also includes an interior surface 195 that is sized andshaped to inhibit radial movement of the split ring 165 and to hold thesplit ring 165 in its operating position. In some constructions, thecollar 170 includes two or more key members (not shown) that extendalong an axis that is parallel to the longitudinal axis 60.

Turning to FIG. 11, the split ring 165 is illustrated as a singleunitary component. However, the split ring 165 is preferably formed fromtwo identical or similar half rings that when put together define thecomplete split ring 165. The split ring 165 includes two cylindricalwall portions 200 that are separated by gaps 205 and that extend from asecond cylindrical portion 210. In some constructions, two or more keyslots 215 are formed in the cylindrical wall portions 200. A taperedbore defines the innermost surface 220 of the second cylindrical portion210. The innermost surface 220 is angled such that it is substantiallyparallel to the jaw aperture 80 when sectioned through the longitudinalaxis 60 and the jaw axes 135. The innermost surface 220 includes threadsthat are arranged to engage the threads of each of the three jaws 100.In addition, the second cylindrical portion 210 includes three jawrecesses 225 that extend radially outward from the innermost surface 220and that are sized to receive the jaws 100.

To assemble the chuck 10, the jaws 100 are positioned within the jawapertures 80 of the chuck body 20. The guide sleeve 95 is slid onto thechuck body 20 and the jaw pins 105 are slid through the pin apertures145 in each of the jaws 100 and into their respective guide sleeveapertures 127. The two halves of the split ring 165 are positionedwithin the slot 70 between the collar portion 50 and the head portion 55of the chuck body 20. The collar 170 is then slid over the head portion55 of the chuck body 20 and into position such that the interior surface195 of the collar 170 holds the split ring 165 together. Inconstructions that include key members on the collar 170, the keymembers are aligned with the key slots 215 in the split ring 165 tofixedly tie the collar 170 and the split ring 165 for rotation. Thesleeve 175 is then attached to the collar 170 and the biasing member 110is positioned such that one end engages the guide sleeve 95. The bottomcover 15 is then threaded onto the chuck body 20 to compress the biasingmember 110 and complete the assembly of the chuck 10.

In operation, the biasing member 110 biases the sliding assembly 25upward such that the jaws 100 are in their closed or smallest sizeposition (the close position), as illustrated in FIG. 2. To insert a bitor other tool, the user first rotates the rotating assembly 30 via thecollar 170 and the sleeve 175 to a free moving position. In thisposition, the recesses 225 of the split ring 165 are aligned with thejaws 100 such that the threads of the jaws 100 are disengaged from thethreads of the split ring 165. With the threads disengaged, the onlyresistance to downward movement of the jaws 100 (i.e., toward the openposition) is provided by the biasing member 110. Thus, the user pushesthe jaws 100 downward such that the jaws 100 are free to open andreceive the tool being inserted. Once the tool is inserted, the biasingmember 110 biases the jaws 100 upward slightly and the central bore 90guides the jaws 100 inward slightly to lightly squeeze the tool. Theuser then rotates the rotating assembly 30 to rotate the split ring 165.As the split ring 165 rotates, the tapered threads of the split ring 165engage the threads of the jaws 100. The thread pitch is arranged suchthat further rotation of the rotating assembly 30 forces the jaws 100upward and inward (i.e., toward the close position) to firmly hold thetool in place. Thus, a user is able to quickly insert a tool into thechuck 10 with very little rotation of the rotating assembly 30. Toremove the tool, the user simply rotates the rotating assembly 30, inthe opposite direction, to the free moving position to disengage thethreads of the split ring 165 from the threads of the jaws 100. The userthen simply pulls the tool from the chuck 10. With the tool removed, thebiasing member 110 biases the jaws 100 to their closed or smallest sizeposition.

FIG. 12 illustrates another auto sizing chuck 10 a that is similar tothe auto sizing chuck 10 of FIG. 1. The auto sizing chuck 10 a includesa plurality of pins 105 that each engages a jaw 100 a and a guide sleeve95 a. Rather than orient the pins 105 so that they are normal to thedirection of movement of the guide sleeve 95, 95 a as they are orientedin FIG. 1, the pins 105 in FIG. 12 are oriented so that they areapproximately normal to the jaw 100 a that the pin 105 engages. Thisarrangement assures that the jaws 100 a do not apply an uneven load tothe pins 105 during movement, as such a load could cause binding orsticking during auto sizing operation.

What is claimed is:
 1. A chuck for a power tool, the chuck comprising: achuck body extending along a longitudinal axis and defining anattachment end and a tool receiving end; a plurality of jaws, each ofthe jaws including a jaw end and a drive end, each of the jaws movablealong a respective jaw axis between a closed position and an openposition, each respective jaw axis oriented at an oblique angle relativeto the longitudinal axis of the chuck body; a biasing member coupled toeach of the jaws and operable to bias the plurality of jaws toward theclosed position, the biasing member including a spring disposed radiallybetween the longitudinal axis of the chuck body and the drive ends ofthe jaws; and a rotating assembly selectively engageable with theplurality of jaws such that, when engaged, the plurality of jaws aremovable in response to rotation of the rotating assembly.
 2. The chuckof claim 1, wherein the rotating assembly includes an engagement portionselectively engageable with each of the plurality of jaws.
 3. The chuckof claim 2, wherein each of the jaws includes threads formed on asurface of each of the jaws, and wherein the engagement portion includesthreads adapted to engage the threads of the jaws.
 4. The chuck of claim1, wherein the biasing member includes a guide sleeve coupled to each ofthe plurality of jaws and movable axially along the longitudinal axis,each of the plurality of jaws moving along the respective jaw axis inresponse to movement of the guide sleeve.
 5. The chuck of claim 4,further comprising a plurality of pins, each pin extending between theguide sleeve and one of the plurality of jaws, the one jaw moving alongthe pin as the one jaw moves between the closed position and the openposition.
 6. The chuck of claim 5, wherein each of the pins defines alongitudinal pin axis and each of the longitudinal pin axes issubstantially normal to the longitudinal axis.
 7. The chuck of claim 5,wherein each of the pins defines a longitudinal pin axis and each of thelongitudinal pin axes is substantially normal to the respective jaw axisof the associated jaw.
 8. The chuck of claim 1, wherein the chuck bodyincludes a plurality of jaw receiving surfaces and each of the pluralityof jaws includes a guide surface engaged with one of the jaw receivingsurfaces to guide movement of the jaw along the respective jaw axis. 9.The chuck of claim 1, wherein the chuck body includes a plurality ofslots, each slot extending along a respective jaw axis and receiving oneof the jaws.
 10. The chuck of claim 1, further comprising a capselectively coupled to the attachment end of the chuck body.
 11. A chuckfor a power tool, the chuck comprising: a chuck body extending along alongitudinal axis and defining an attachment end and a tool receivingend; a plurality of jaws, each of the jaws including a first engagementportion, a jaw end, and a drive end, each of the jaws movable along arespective jaw axis between a closed position and an open position, eachrespective jaw axis oriented at an oblique angle relative to thelongitudinal axis of the chuck body; a biasing member coupled to theplurality of jaws and operable to bias the plurality of jaws toward theclosed position, the biasing member including a spring positionedradially between the longitudinal axis of the chuck body and the driveends of the jaws; and a rotating assembly coupled to the chuck body androtatable with respect to the chuck body between a disengaged position,an engaged position, and a tightened position, the rotating assemblyincluding a second engagement portion, the first engagement portion andthe second engagement portion being disengaged when the rotatingassembly is in the disengaged position, the first engagement portionsand the second engagement portion being engaged when the rotatingassembly is in the engaged position such that each of the jaws ismovable along its respective jaw axis in response to rotation of therotating assembly, and rotation of the rotating assembly from theengaged position to the tightened position moves the plurality of jawstoward the closed position.
 12. The chuck of claim 11, wherein the chuckbody includes a cylindrical guide surface having an outer diameter, andwherein the biasing member further includes a guide sleeve movablyengaging the cylindrical guide surface.
 13. The chuck of claim 11,wherein the first engagement portion includes threads formed on asurface of each of the jaws, and wherein the second engagement portionincludes threads adapted to engage the threads of the jaws.
 14. Thechuck of claim 11, wherein the biasing member further includes a guidesleeve coupled to each of the plurality of jaws and movable axiallyalong the longitudinal axis, each of the plurality of jaws moving alongthe respective jaw axis in response to movement of the guide sleeve. 15.The chuck of claim 14, further comprising a plurality of pins, each pinextending between the guide sleeve and one of the plurality of jaws, theone jaw moving along the pin as the one jaw moves between the closedposition and the open position.
 16. The chuck of claim 15, wherein eachof the pins defines a longitudinal pin axis and each of the longitudinalpin axes is substantially normal to the longitudinal axis.
 17. The chuckof claim 15, wherein each of the pins defines a longitudinal pin axisand each of the longitudinal pin axes is substantially normal to therespective jaw axis of the associated jaw.
 18. The chuck of claim 11,wherein the chuck body includes a plurality of jaw receiving surfacesand each of the plurality of jaws includes a guide surface engaged withone of the jaw receiving surfaces to guide movement of the jaw along therespective jaw axis.
 19. The chuck of claim 11, wherein the plurality ofjaws are movable independent of the rotating assembly when the rotatingassembly is in the disengaged position.
 20. A method of engaging a toolin a chuck, the method comprising: movably positioning a plurality ofjaws within a chuck body, the jaws movable between a close position andan open position; disengaging a rotating assembly from the plurality ofjaws; moving the jaws to the close position in response to thedisengagement of the rotating assembly from the plurality of jaws;pushing the jaws toward the open position until the tool can bepositioned within the jaws; biasing the jaws toward the close positionsuch that the jaws lightly hold the tool in a desired position; rotatingthe rotating assembly to engage the rotating assembly and the pluralityof jaws; further rotating the rotating assembly to force the jaws towardthe close position to firmly hold the tool in the desired position; andmaintaining the position of the rotating assembly to hold the pluralityof jaws in the desired position.